Theorem dfrals2 50448

Description: The bounded "all some" form is the general form with the class membership folded into the antecedent. (Contributed by David A. Wheeler, 22-Oct-2018.) (Revised by David A. Wheeler, 12-Jul-2026.)

Assertion

Ref	Expression
dfrals2	⊢ (∀∃𝑥 ∈ 𝐴(𝜑 → 𝜓) ↔ ∀∃𝑥((𝑥 ∈ 𝐴 ∧ 𝜑) → 𝜓))

Proof of Theorem dfrals2

Step	Hyp	Ref	Expression
1		df-ral 3086	. . . 4 ⊢ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ↔ ∀𝑥(𝑥 ∈ 𝐴 → (𝜑 → 𝜓)))
2		impexp 455	. . . . 5 ⊢ (((𝑥 ∈ 𝐴 ∧ 𝜑) → 𝜓) ↔ (𝑥 ∈ 𝐴 → (𝜑 → 𝜓)))
3	2	albii 1846	. . . 4 ⊢ (∀𝑥((𝑥 ∈ 𝐴 ∧ 𝜑) → 𝜓) ↔ ∀𝑥(𝑥 ∈ 𝐴 → (𝜑 → 𝜓)))
4	1, 3	bitr4i 281	. . 3 ⊢ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ↔ ∀𝑥((𝑥 ∈ 𝐴 ∧ 𝜑) → 𝜓))
5		df-rex 3096	. . 3 ⊢ (∃𝑥 ∈ 𝐴 𝜑 ↔ ∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜑))
6	4, 5	anbi12i 639	. 2 ⊢ ((∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ∧ ∃𝑥 ∈ 𝐴 𝜑) ↔ (∀𝑥((𝑥 ∈ 𝐴 ∧ 𝜑) → 𝜓) ∧ ∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜑)))
7		df-rals 50447	. 2 ⊢ (∀∃𝑥 ∈ 𝐴(𝜑 → 𝜓) ↔ (∀𝑥 ∈ 𝐴 (𝜑 → 𝜓) ∧ ∃𝑥 ∈ 𝐴 𝜑))
8		df-als 50446	. 2 ⊢ (∀∃𝑥((𝑥 ∈ 𝐴 ∧ 𝜑) → 𝜓) ↔ (∀𝑥((𝑥 ∈ 𝐴 ∧ 𝜑) → 𝜓) ∧ ∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜑)))
9	6, 7, 8	3bitr4i 306	1 ⊢ (∀∃𝑥 ∈ 𝐴(𝜑 → 𝜓) ↔ ∀∃𝑥((𝑥 ∈ 𝐴 ∧ 𝜑) → 𝜓))

Syntax hints:   → wi 4   ↔ wb 209   ∧ wa 400  ∀wal 1565  ∃wex 1806   ∈ wcel 2149  ∀wral 3085  ∃wrex 3095  ∀∃wals 50444  ∀∃wrals 50445

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1822  ax-4 1836

This theorem depends on definitions:  df-bi 210  df-an 401  df-ral 3086  df-rex 3096  df-als 50446  df-rals 50447

This theorem is referenced by:  rals-no-surprise  50465